酸枣花蜜腺的解剖学研究

Anatomical Studies on Floral Nectary in Ziziphus Jujuba var. spinosa

酸枣的花蜜腺环绕在子房基部的周围，属花盘蜜腺，由分泌表皮和泌蜜组织构成，花托维管束末端终止于泌蜜组织基部。分泌表皮外覆盖有较厚的角质层。蜜腺下方薄壁组织中分布有大的粘液腔和含单宁细胞，据组化测验，粘液腔中含有大量的多糖物质，可能与原蜜汁的来源有关。在花的发生和发育过程中，花盘有其自身的原始细胞，但蜜腺是由花盘表层细胞分化而来。原蜜汁来源于维管束末端韧皮部，经泌蜜组织加工成蜜汁，分泌到气孔下腔，最后通过张开的气孔泌出体外。

The floral nectary round the base of ovary in Ziziphus jujuba var, spinosa belong to disc nectary,composed of secretory epidermis and ncetariferous tisstie. The vascular bundle of receptacle stretches to the base of nectariferous tissue. Cuticle coveres the secretory epidermis. There were many mucilage cavitys and tannin cells in parenchyma beneath the nectary. The mucilage cavity contains lotof polysaccharose which may relate to origination of pronectar. Disc had itsown initial cells, but nec-tary originates from some epidermal and hypodermal cells of disc during ontogeny of flower. The nec-tar is formed in the nectariferous tissue,then transported to the subsomatal chamber and exuded final-ly out of the nectary surface via modified stomata.